1. Field of the Invention
The present invention relates generally to a battery device in a mobile terminal and an operating method thereof, and in particular, to a battery device for use in a mobile terminal, for automatically detaching a battery from the mobile terminal to prevent an accident caused by battery overheating, and a method of operating the battery device.
2. Description of the Related Art
Mobile terminals for providing mobile communication services, such as CDMA (Code Division Multiple Access), GSM (Global System for Mobile communication), PCS (Personal Communications Service), and PDA (Personal Digital Assistant) phones, are provided with detachable batteries for supplying standby power or operational power. The detachable batteries allow users to carry the mobile terminals conveniently and use them at any place. A mobile terminal is typically provided with such a battery on one side thereof, for power supply, and the battery will have a different size according to its capacity.
The mobile terminal needs DC (Direct Current) power to operate. The DC power is externally provided to the mobile terminal and, at the same time, it is converted to a predetermined current through a predetermined control and charges the battery. The battery is a typically rechargeable, generally of a NiCd (Nickel-Cadmium), NiMH (Nickel-Metal-Hydride) or Li Ion (Lithium-Ion) type.
Mobile terminals have much circuitry, often include many devices, and emit much heat during a call. A NiCD or Li Ion battery is usually used for the mobile terminal. If a call lasting a long time is made through the mobile terminal, the battery will heat up and, in turn, will heat the mobile terminal. This heat from the battery, along with the heat generated inside the terminal, can cause malfunction or communication failure and, at worst, a battery explosion.
When an abnormal condition such as an overcurrent condition overheats the battery, the overheating may occur while the battery is installed in the mobile terminal, which includes a risk of the battery exploding.
Since the battery should be portable and easily carried in view of the nature of its use, batteries for mobile terminals are typically made as thin and lightweight as possible. As a result, there is a probability that the battery may be damaged or even may explode due to heat from the chemical reaction among electrolytes or due to external shock-incurred mixing of the electrolytes during charging/discharging of the battery. Hence, there is a need for a system that senses a change in temperature inside the battery and ensures the safety of the battery by providing a control signal that corresponds with the temperature change.